This invention relates to doors having a window portion and more particularly to such doors in which the window portion is easily replacable.
Windowed doors are well known and are commonly employed as a safety measure for swinging doors and the like, and particularly for those used in heavily trafficked areas. While the windows in such doors may be installed by conventional means, such as glazier's points and glazing compound, the heavy use of frequently used doors subjects the windows to potential damage, and ease of replacement of the window becomes an important concern. Such concerns are answered in part by doors accommodating framed window units, the entire framed unit being secured to the door, as by screws and being removable as a whole. Alternatively, transparent plastic sheeting which may itself be secured to the door by screws, has been used. An example of the latter type of door is disclosed in U.S. Pat. No. 3,325,943.
Aside from requiring the use of tools for the replacement of a window, such designs also require a replacement window. This may be disadvantageous in applications in which the door is used as an environmental barrier, such as the door to a cold room, clean room, or the like. While a user might stock spare windows, unless such spares are readily available, if the window in such a door becomes damaged either the visibility through the window or the environmental barrier provided by it must be sacrificed until a replacement window can be secured.
Accordingly, it is an object of the present invention to provide a windowed door in which the window pane may be readily removed and replaced with a minimum use of tools, and in which a damaged window pane may be manipulated so as to provide a temporary replacement window.